Henriquez, 26, of Deer Park, has a rare, chronic kidney condition that has caused her twin waste-filtering organs to fail. She requires kidney dialysis to sustain her health and life. During her pregnancy, she went from three to six days a week on dialysis.

The case, however, is a gigantic leap forward for medicine. Most women on dialysis are advised against pregnancy.

"When she was 15 weeks pregnant, I put her on dialysis in an attempt to give her as normal a pregnancy as possible," Miller said. "It is a very, very precarious medical situation to be on dialysis while pregnant."

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This case proves that it is medically possible to have renal failure, be on dialysis and deliver a healthy baby, Miller said.

Henriquez, meanwhile, was beaming Thursday as she cuddled her month-old son.

"I am obviously excited," Henriquez said. She and her husband, Manny, have "two healthy children. . . . It's really nice to hear that my situation might open doors to some different possibilities for other women."

So few women have completed a successful pregnancy while on dialysis that the medical literature has only eight documented cases, Miller explained Thursday as she called for a national registry -- a database -- to track patients and their outcomes.

Miller called Kaylee and baby Mateo remarkable for pulling through in great spirits and good health after a medically intense, nine-month ordeal.

"I am delighted," Miller said, "and hopefully at some point Kaylee will get a transplant. I can't put her on it [the organ-transplant waiting list] right now because she's too close to the pregnancy. But that is the plan for the future."

Henriquez has a condition known as IGG-IGM glomerulonephritis, an exceptionally rare kidney disorder that causes swelling of extremities and soaring blood pressure.

Beyond the cases in the medical literature, the National Kidney Foundation carries a lengthy discussion on its website warning about the dangers of being pregnant while on dialysis.

Women with severe kidney disease are often cautioned to terminate their pregnancies, and that was the initial advice Henriquez received three years ago during her first pregnancy when she saw doctors in New York City.

Determined to be a mom -- at whatever cost -- she sought the help of North Shore doctors.

"I wasn't on dialysis the first time, my condition didn't warrant it, but I was on steroids and I was very sick during that pregnancy," she said. "Isabella was born at 31 weeks."